1. Field of the Invention
The present invention relates to a substrate supporting apparatus that moves between vacuum chambers while supporting a substrate, an inline-type substrate processing apparatus that hermetically connects a plurality of vacuum chambers, a substrate supporting method, a control program of the substrate supporting apparatus, and a recording medium.
2. Description of the Related Art
In an inline-type substrate processing apparatus, a plurality of vacuum chambers including process chambers that form a thin film is hermetically connected. The inline-type substrate processing apparatus includes a substrate supporting apparatus (carrier) that moves between vacuum chambers while supporting a substrate so that vacuum film formation processing is continuously performed on the substrate. From the viewpoint of improving productivity, the substrate supporting apparatus is provided with a disc-like pallet that is rotatable by being mounted with a plurality of substrates and is configured to be able to form a thin film from both sides of the substrate at the same time while holding the pallet in a vertical posture.
As a related technology, a substrate supporting apparatus that is provided with a pallet capable of being mounted with one or more substrates and rotatably supports a center section of the pallet by a rotation supporting mechanism fixed onto a carrier capable of performing a translation via a support medium is proposed (see Japanese Patent Application Laid-Open No. 07-15773 (FIG. 1)). The substrate supporting apparatus is provided with the rotation supporting mechanism in the center section of a second support medium hooked to a first support medium fixed to the carrier and has a structure in which the pallet and the substrate supporting apparatus are not separable.
However, according to the technology of Japanese Patent Application Laid-Open No. 07-15773, the pallet and the substrate supporting apparatus are structured integrally so that it is necessary to mount a rotation supporting mechanism on the supporting apparatus and it is impossible to mount a large rotation driving source and improve the rotational speed. Moreover, pallet replacement is complicated, the apparatus becomes heavier and has a more complex structure, and the carrying speed between vacuum chambers becomes slower. Therefore, it is difficult to improve productivity of an inline-type substrate processing apparatus.
Thus, a substrate supporting apparatus that adopts a structure in which a fulcrum with a rotation function is mounted on a carrier and a pallet is only put on the fulcrum with a rotation function and includes a lift mechanism to lift the pallet to be separated from the carrier and a mechanism that rotatably holds the center section of the pallet in a process chamber can be considered.
According to the apparatus, the pallet and the substrate supporting apparatus are structured to be separable and thus, a structure capable of dealing with various problems concerning Japanese Patent Application Laid-Open No. 07-15773 is provided, but new problems described below arise.
That is, a film is formed while the pallet is separated from the carrier after the pallet on the fulcrum with a rotation function is caused to rise by the lift mechanism set up inside the process chamber while an outer diameter part of the pallet being gripped and the center section of the pallet is rotatably held by a pallet holding/driving mechanism set up inside the chamber. However, since the inner part of the chamber is a high-temperature environment of 100 to 300° C., the outer diameter of the pallet thermally expands with a rising temperature of the pallet and the center position thereof also rises. Accordingly, the pallet holding/driving mechanism does not work normally due to a shifted center position of the pallet during an ascent and descent operation by the lift mechanism, posing a problem that the pallet cannot be held. Moreover, it takes a long time to operate the lift, posing an obstacle to improvement of production tact. Therefore, it is necessary to devise a method of operating the lift such as using adjustments of the lifting position depending on each process condition.
Moreover, the pallet is only put on the fulcrum with a rotation function in this structure. Thus, there is a problem that when an operation abnormality of the mechanism such as an abnormal lift operation and an abnormal pallet holding operation occurs, a carrying abnormality such as a fall of the pallet from the fulcrum with a rotation function occurs, and even without such a fall, and a shift of the holding position occurs. Accordingly, there is a problem of low productivity that an abnormality is more likely to occur in the next process and in some circumstances, maintenance is needed after stopping the production.
In view of the above circumstances, an object of the present invention is to provide a substrate supporting apparatus capable of increasing reliability of pallet holding and reliability of operations by improving a pallet holding structure and improving productivity by preventing carrying abnormalities and an inline-type substrate processing apparatus equipped with such a substrate supporting apparatus.
Further, the present invention provides a substrate supporting method capable of achieving the above object, a control program, and a recording medium.